News

Sep 17, 2012

Passive House approach catches on in Canada

Passive Houses use about 90% less energy than conventionally-designed houses

When the world visited Whistler for the 2010 Olympics, a new breed of building greeted them. Austria House, used by the Austrian Olympic Committee and public broadcaster, was the first house in Canada to be built according to Passive House principles.

After the Olympics, the 2,700 square foot house was gifted to the municipality, and is now operated as Lost Lake PassivHaus, used as a day lodge, office and meeting space, a location for ski and bike rentals, and a food counter.

Passive House is a standard for extremely high energy efficiency, and Lost Lake house is proving what a difference that can make. The public building consumes just $233 in electricity for heat — for a full year of operation.

Design makes the difference

The initiator of Austria House, Guido Wimmers, says Passive House is an integrated design process that brings together all elements of planning.

"I worked quite a while in a large architectural office, on large commercial buildings," he says of his early career. "I'm over-simplifying, but basically, the approach was that you design something and then you ship the drawings over to your mechanical engineer, and tell him, 'Now, please make it energy efficient.' But that doesn't work."

By contrast, the Passive House approach optimizes the building's shell first, to the point where the need for mechanical heating and cooling systems are reduced significantly. Wimmers says an efficient shape, thicker walls and roof, and a careful eye to orientation to the sun, also create better interior comfort.

"You get a very stable, comfortable climate on the inside, no cold surfaces, no drafts,"he says. "And it's healthy because air exchange is well balanced. There are a lot of benefits, not just saving money on energy but also in terms of healthy living, thermal comfort, and noise reduction."

To be certified as a Passive House, a building must meet several performance standards, including 0.6 air changes per hour in a blower door test, and a rigourous criteria for primary energy demand — a calculation including heating, cooling, domestic hot water, and plug loads.

Most importantly, it must not use more than 15 kWh per square meter for heating — about a tenth of the average B.C. home. Although it is hard to compare to the more commonly used EnerGuide rating, Wimmers says most Passive House buildings would achieve EG 90-95.

Passive Houses use about 90% less energy than conventional buildings.

"The goal first of all with Passive House is to reduce the overall energy demands, not necessarily to focus on the type of energy, such as renewables," says Wimmers. "You can heat your Passive House with gas, if you like."

The point is, you won't need very much.

Canadian leadership comes home

In 2010, Wimmers and others launched the Canadian Passive House Institute to provide training to the Canadian building industry. Since then, 250 people have taken courses in passive house fundamentals, and Wimmers says across the country there are now about 40 Passive House builds in the pipeline.

Although Wimmers credits Canada with some early leadership in high-efficiency design (through the nearly-forgotten Saskatchewan House of 1977), the Passive House standard originated in Europe, where most of the world's approximately 40,000 certified buildings are located.

Increasing adoption is bringing down the price premium associated with higher-quality design. While Passive House in Canada is estimated to cost about 10% more than conventional building (similar to Europe 15 years ago), Wimmers says the additional cost of Passive House in Europe is now between 2 and 5%.

Around the world, Passive House buildings now exist in about 38 countries. Wimmers sees it as an approach that will continue to catch on.

"In countries like Austria, it's already the case that every public building, has to be built following Passive House standards," he says. "The building industry is a bit slow-moving compared to others, but it's not a question of whether this type of high-efficiency building will be widely adopted — it's just a question of how quickly."